Which RIB & engine?

[Bulawayo]

First, many 15hp engines are tuned 10hp. For any dinghy and outboard it can be worth adding dinghy wheels. I could not drag my outfit up the beach solo without them. Good luck with your selection.

[j.g.evans]

I cruised the Bahamas many years with an AL RIB with a 15 HP and a 3.3 HP engine. The AL RIB was advertised as 70 lbs; but, it was closer to 100 lbs. I recommend a 2 cycle 15 HP engine for you will need the HP to plane with 2 people and supplies. If you are not planing then you will be wet. The 2 cycle 15 weighs the same as 9.6 HP. I rigged a crane on my wind generator pole and later on a custom arch to hoist the engine to the stern rail. I used the 3.3 HP for short distances and was able to manually lift it to the boat. I lifter the dinghy on davits every night and for passages. I felt that it would be more difficult to steal the dinghy on davits. I never had the motors on the dinghy for passages. Lifting the dinghy with a motor with a 4:! block system was hard and the shock load under way would be fierce. I had a custom arch made with built in davits (motor crane and solar panels too) so I could raise the dinghy low and high. With typical low davits, I found that the dinghy would scoop up water when the boat is healed in heavy seas.

[SY Kelpie]

Originally Posted by j.g.evans

The 2 cycle 15 weighs the same as 9.6 HP.

Surely that depends on the specific make and model?
I have my eye on the Tohatsu 9.8hp 2 stroke which weighs as little as 26kg.
What's the lightest 15hp available?

[malbert73]

We just chartered with a high field UL290 with a Tohatsu 2 stroke 9.8. Could plane with me and 2 kids (275 lbs) but if all 4 of us on board it couldn’t (425 lbs of crew) except once downwind

[SY Kelpie]

Originally Posted by malbert73

We just chartered with a high field UL290 with a Tohatsu 2 stroke 9.8. Could plane with me and 2 kids (275 lbs) but if all 4 of us on board it couldn’t (425 lbs of crew) except once downwind

Thanks, that's useful info.
Our all up weight will be somewhere between your two numbers- obviously our son will continue to grow so looking ahead a few years I would guess our all up crew weight to be in the region of 365lbs.
The UL290 is exactly the kind of RIB we are considering, as well.

[Dockhead]

Originally Posted by SY Kelpie

. . . I have my eye on the Tohatsu 9.8hp 2 stroke which weighs as little as 26kg.
What's the lightest 15hp available?

I've also had my eye on this, as it is astonishingly light, a kilo less than my 8hp Selva. But where you can you buy it in the UK?

[SY Kelpie]

Originally Posted by Dockhead

I've also had my eye on this, as it is astonishingly light, a kilo less than my 8hp Selva. But where you can you buy it in the UK?

Most Tohatsu dealers will sell one to a commercial user. I'm not sure if they are allowed to supply to a yacht that is in the process of leaving the country.
Alternatively you can buy them from Mainbrayce chandlers in Alderney.

Since posting to ask about lightweight 15hp motors, I've come across the Selva Naxos which is supposedly only 30kg and is considerably cheaper than the Tohatsu- mixed reviews though.

[a64pilot]

Originally Posted by SY Kelpie

Surely that depends on the specific make and model?

I have my eye on the Tohatsu 9.8hp 2 stroke which weighs as little as 26kg.

What's the lightest 15hp available?

The Yamaha leisure, not Enduro 15 hp is about 75 lbs I think.

[Montanan]

To improve planning ability and / or to accommodate a smaller RIBs and lower powered outboards consider adding Lifters, which are specially design trib tabs for dinghys.

http://http://www.maximarine.com/pro...ers/index.html

"LIFTERSTM radically improve the performance of inflatable boats, increasing speed and acceleration 25% to 45% and planing weight capacity up to 30%, while decreasing fuel consumption by over 25%. Boats having insufficient power or carrying heavy loads can now plane or achieve higher planing speeds."

https://www.youtube.com/watch?v=xrIehHGrEW0

[Pelagic]

Originally Posted by SY Kelpie

Thanks again for all the suggestions, advice, and ideas.
There seems to be a consensus around the idea of an ali hulled hypalon RIB of about 3m, with a 10hp minimum engine. This is kind of what I was expecting, although I had heard some anecdotes about getting by with just a 6hp.

I'm really quite reluctant to go above 10hp, primarily for weight reasons. The right RIB and a 2st Tohatsu 9.8 could be as little as 60kg all up, which is viable for the two of us to lift/drag a short distance. Anything heavier than that just doesn't sound realistic.

I think you are on the right track size wise to give you versatility and security to explore.

We dive, so speed and range to get out thru passes to dive outer reefs carrying 2 people + gear is one of our priorities

I like Aloy bottom and transom for carrying up the beach vs heavier Fiberglass. It is not just about lifting onboard

This us my Hypalon Achilles tender.....still going strong after 19 years but it was always covered when not in use and has sacraficial chaps which have been replaced twice


http://www.achillesboats.com/boatmodels/commercial/

I have always used a 15hp 2 stroke Yamaha Enduro because it is the most popular world wide with commercial guys and parts are always available.
Just bought a new one last week in the Philippines

I dont believe there is any weight difference between the 9.9hp & 15hp and the 15 will easily get 2 divers onto a plane in flat water.

For me, like DH, I anchor in deeper water, away from the mosquitos so I think its fair to say that the size and quality of your tender has a big impact on your cruising life.

[Pelagic]

Originally Posted by Montanan

To improve planning ability and / or to accommodate a smaller RIBs and lower powered outboards consider adding Lifters, which are specially design trib tabs for dinghys.

http://http://www.maximarine.com/pro...ers/index.html

"LIFTERSTM radically improve the performance of inflatable boats, increasing speed and acceleration 25% to 45% and planing weight capacity up to 30%, while decreasing fuel consumption by over 25%. Boats having insufficient power or carrying heavy loads can now plane or achieve higher planing speeds."

That is really an improvement... Just wondering, with all that extra lift force on the transom, if the outboard clamps worked loose, is their an added danger of the OB lifting up and flying off the stern?

[storx]

I dont currently live on a boat, but i still have my dads old dingy from before he passed away that i use for fishing from time to time, its extremely portable and easy to store when not in use, Its called "Porta-Boat", i have a small Nissan outboard to power it and it is plenty to get around easily with a full boat of stuff.

[storx]

I miss spoke, its actually called "Porta-Bote"